U.S. patent application number 15/167341 was filed with the patent office on 2017-07-06 for display device, touch sensing circuit, and driving method.
The applicant listed for this patent is LG Display Co., Ltd.. Invention is credited to SoonDong CHO, Hoon JANG, Wonyong JANG.
Application Number | 20170192608 15/167341 |
Document ID | / |
Family ID | 59069039 |
Filed Date | 2017-07-06 |
United States Patent
Application |
20170192608 |
Kind Code |
A1 |
JANG; Hoon ; et al. |
July 6, 2017 |
Display Device, Touch Sensing Circuit, and Driving Method
Abstract
The present embodiments relate to a display device, a touch
sensing circuit, and a driving method, and more specifically, to a
display device, a touch sensing circuit, and a driving method,
which may: detect the power mode; create touch driving signals that
have different amplitudes depending on the detected power mode; and
drive touch electrodes for sensing the touch by using the created
touch driving signals in order to thereby provide a high touch
sensitivity regardless of the type of power mode.
Inventors: |
JANG; Hoon; (Goyang-si,
KR) ; CHO; SoonDong; (Gumi-si, KR) ; JANG;
Wonyong; (Bucheon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG Display Co., Ltd. |
Seoul |
|
KR |
|
|
Family ID: |
59069039 |
Appl. No.: |
15/167341 |
Filed: |
May 27, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/044 20130101;
G06F 2203/04103 20130101; G06F 1/3262 20130101; G06F 2203/04102
20130101; G06F 3/0418 20130101; G06F 3/0412 20130101 |
International
Class: |
G06F 3/041 20060101
G06F003/041; G06F 1/32 20060101 G06F001/32; G06F 3/044 20060101
G06F003/044 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 31, 2015 |
KR |
10-2015-0190726 |
Claims
1. A display device comprising: a display panel having one or more
touch electrodes embedded therein; a first circuit to generate a
touch driving signal at an output of the first circuit, wherein at
the output of the first circuit the touch driving signal has a
first amplitude during a first power mode and a second amplitude
different than the first amplitude during a second power mode; and
a second circuit having an input coupled to the output of the first
circuit, the second circuit to provide the touch driving signal to
the one or more touch electrodes.
2. The display device of claim 1, wherein the first power mode is a
battery power mode and the second power mode is an adapter power
mode, and the first amplitude of the touch driving signal at the
output of the first circuit during the battery power mode is
greater than the second amplitude of the touch driving signal at
the output of the first circuit during the adapter power mode.
3. The display device of claim 1, further comprising: a backlight
driver having an input power voltage, wherein the first power mode
corresponds to when the input power voltage is a first voltage
level, and the second power mode corresponds to when the input
power voltage is a second voltage level different than the first
voltage level.
4. The display device of claim 1, wherein, when the display device
switches from the first power mode to the second power mode, the
first circuit initially generates the touch driving signal to have,
at the output of the first circuit, an intermediate amplitude
between the first amplitude and the second amplitude, and then
generates the pulse signal to have the second amplitude at the
output of the first circuit.
5. The display device of claim 4, wherein, when the display device
switches from the second power mode to the first power mode, the
first circuit initially generates the touch driving signal to have
the intermediate amplitude at the output of the first circuit, and
then generates the touch driving to have the first amplitude at the
output of the first circuit.
6. The display device of claim 1, wherein the first circuit
controls an amplitude of the touch driving signal based on an
amplitude control signal, and the display device further comprises:
a third circuit that detects whether the display device is in the
first power mode or the second power mode, and generates the
amplitude control signal based on whether the display device is in
the first power mode or the second power mode.
7. The display device of claim 6, wherein the third circuit detects
whether the display device is in the first power mode or the second
power mode based on an input power voltage of a backlight
driver.
8. The display device of claim 6, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; an integrator
circuit configured to output an integral value of a voltage of the
output terminal; and an analog-to-digital converter configured to
convert an output voltage of the integrator circuit into a digital
value, wherein the third circuit generates the amplitude control
signal further based on the digital value.
9. The display device of claim 6, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; a feedback
capacitor connected between the first terminal and the output
terminal; an integrator circuit configured to output an integral
value of a voltage of the output terminal; and an analog-to-digital
converter configured to convert an output voltage of the integrator
circuit into a digital value, wherein the third circuit generates
the capacitance control signal for controlling the capacitance of
the feedback capacitor.
10. The display device of claim 6, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; an integrator
circuit configured to output an integral value of a voltage of the
output terminal; and an analog-to-digital converter configured to
convert an output voltage of the integrator circuit into a digital
value, wherein the third circuit generates an integrator control
signal for controlling a number of integration times of the
integrator circuit.
11. The display device of claim 6, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; an integrator
circuit configured to output an integral value of a voltage of the
output terminal; and an analog-to-digital converter configured to
convert an output voltage of the integrator circuit into a digital
value, wherein the third circuit adds a correction value to a
sensed value output from the analog-to-digital converter to
generate a corrected sensed value and generates touch coordinates
based on the corrected sensed value, the correction value generated
to have a first value during the first power mode and a second
value during the second power mode.
12. A driver circuit for driving a touch sensitive display device
including a display panel having one or more touch electrodes
embedded therein, the driving circuit comprising: a first circuit
to generate a touch driving signal at an output of the first
circuit, wherein at the output of the first circuit the touch
driving signal has a first amplitude during a first power mode and
a second amplitude different than the first amplitude during a
second power mode; and a second circuit having an input coupled to
the output of the first circuit, the second circuit to provide the
touch driving signal to the one or more touch electrodes.
13. The driver circuit of claim 12, wherein the first power mode is
a battery power mode and the second power mode is an adapter power
mode, and the first amplitude of the touch driving signal at the
output of the first circuit during the battery power mode is
greater than the second amplitude of the touch driving signal at
the output of the first circuit during the adapter power mode.
14. The driver circuit of claim 12, wherein the first power mode
corresponds to when an input power voltage of a backlight driver is
a first voltage level, and the second power mode corresponds to
when the input power voltage is a second voltage level different
than the first voltage level.
15. The driver circuit of claim 12, wherein, when switching from
the first power mode to the second power mode, the first circuit
initially generates the touch driving signal to have, at the output
of the first circuit, an intermediate amplitude between the first
amplitude and the second amplitude, and then generates the touch
driving signal to have the second amplitude at the output of the
first circuit.
16. The driver circuit of claim 15, wherein, when switching from
the second power mode to the first power mode, the first circuit
initially generates the touch driving signal to have the
intermediate amplitude at the output of the first circuit, and then
generates the touch driving signal to have the first amplitude at
the output of the first circuit.
17. The driver circuit of claim 12, wherein the first circuit
controls an amplitude of the touch driving signal based on an
amplitude control signal, and the display device further comprises:
a third circuit that detects whether the display device is in the
first power mode or the second power mode, and generates the
amplitude control signal based on whether the display device is in
the first power mode or the second power mode.
18. The driver circuit of claim 17, wherein the third circuit
detects whether the display device is in the first power mode or
the second power mode based on an input power voltage of a
backlight driver.
19. The driver circuit of claim 17, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; an integrator
circuit configured to output an integral value of a voltage of the
output terminal; and an analog-to-digital converter configured to
convert an output voltage of the integrator circuit into a digital
value, wherein the third circuit generates the amplitude control
signal further based on the digital value.
20. The driver circuit of claim 17, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; a feedback
capacitor connected between the first terminal and the output
terminal; an integrator circuit configured to output an integral
value of a voltage of the output terminal; and an analog-to-digital
converter configured to convert an output voltage of the integrator
circuit into a digital value, wherein the third circuit generates
the capacitance control signal for controlling the capacitance of
the feedback capacitor.
21. The driver circuit of claim 17, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, a second terminal to receive
the touch driving signal, and an output terminal; an integrator
circuit configured to output an integral value of a voltage of the
output terminal; and an analog-to-digital converter configured to
convert an output voltage of the integrator circuit into a digital
value, wherein the third circuit generates an integrator control
signal for controlling a number of integration times of the
integrator circuit.
22. The driver circuit of claim 17, wherein the second circuit
comprises: an amplifier including a first terminal electrically
connected with the touch electrode, to receive the touch driving
signal, and an output terminal; an integrator circuit configured to
output an integral value of a voltage of the output terminal; and
an analog-to-digital converter configured to convert an output
voltage of the integrator circuit into a digital value, wherein the
third circuit adds a correction value to a sensed value output from
the analog-to-digital converter to generate a corrected sensed
value and generates touch coordinates based on the corrected sensed
value, the correction value generated to have a first value during
the first power mode and a second value during the second power
mode.
23. A method of driving a touch sensitive display device including
a display panel having one or more touch electrodes embedded
therein, the method comprising: generating a touch driving signal
at an output of a first circuit, wherein at the output of the first
circuit the touch driving signal has a first amplitude during a
first power mode and a second amplitude different than the first
amplitude during a second power mode; and providing, by a second
circuit having an input coupled to the output of the first circuit,
the touch driving signal to the one or more touch electrodes.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from and the benefit under
35 U.S.C. .sctn.119(a) of Korean Patent Application No.
10-2015-0190726, filed on Dec. 31, 2015, which is hereby
incorporated by reference for all purposes as if fully set forth
herein.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present embodiments relate to a display device, a touch
sensing circuit, and a driving method.
[0004] 2. Description of the Related Art
[0005] With the development of the information society, demand is
growing for display devices in a variety of forms in order to
display images. In recent years, various display devices have been
utilized, such as a liquid crystal display device (LCD), a plasma
display panel (PDP), or an organic light emitting display device
(OLED).
[0006] Such display devices include display devices {such as,
laptop computers, tablets, or smart phones (i.e., mobile devices)}
that provide a touch sensing function and adopt two or more power
supply means, such as a battery and an adapter.
[0007] These display devices are supplied with power from any one
of two or more power supply means in order to thereby perform a
touch sensing operation.
[0008] However, the conventional display devices exhibit a
phenomenon in which the touch sensitivity is significantly
different depending on which power supply means supplies the power
during the touch sensing operation.
[0009] In particular, the supply of the power from the battery
brings about a significant reduction in the touch sensitivity
during the touch sensing operation compared to the supply of the
power through the adapter.
SUMMARY
[0010] The present embodiments may provide a touch drive that is
differentiated according to the power mode in order to thereby
improve the touch sensitivity.
[0011] In addition, the present embodiments may prevent the
degradation of the touch sensitivity when the power mode
corresponds to the battery mode.
[0012] Furthermore, the present embodiments may improve the touch
sensitivity through an adaptive touch drive when the power mode is
changed.
[0013] In one embodiment, a display device comprises a display
panel having one or more touch electrodes embedded therein. A
driving circuit of the display device includes a first circuit to
generate a touch driving signal at an output of the first circuit.
At the output of the first circuit the touch driving signal has a
first amplitude during a first power mode and a second amplitude
different than the first amplitude during a second power mode. A
second circuit of the driving circuit has an input coupled to the
output of the first circuit and that provides the touch driving
signal to the one or more touch electrodes.
[0014] In one embodiment, the first power mode is a battery power
mode and the second power mode is an adapter power mode. The first
amplitude of the touch driving signal at the output of the first
circuit during the battery power mode is greater than the second
amplitude of the touch driving signal at the output of the first
circuit during the adapter power mode.
[0015] In one embodiment, the display device includes a backlight
driver having an input power voltage. The first power mode
corresponds to when the input power voltage is a first voltage
level, and the second power mode corresponds to when the input
power voltage is a second voltage level different than the first
voltage level.
[0016] In one embodiment, when the display device switches from the
first power mode to the second power mode, the first circuit
initially generates the touch driving signal to have, at the output
of the first circuit, an intermediate amplitude between the first
amplitude and the second amplitude, and then generates the pulse
signal to have the second amplitude at the output of the first
circuit. When the display device switches from the second power
mode to the first power mode, the first circuit initially generates
the touch driving signal to have the intermediate amplitude at the
output of the first circuit, and then generates the touch driving
to have the first amplitude at the output of the first circuit.
[0017] In one embodiment, the first circuit controls an amplitude
of the touch driving signal based on an amplitude control signal.
The display device also comprises a third circuit that detects
whether the display device is in the first power mode or the second
power mode, and generates the amplitude control signal based on
whether the display device is in the first power mode or the second
power mode. The third circuit detects whether the display device is
in the first power mode or the second power mode based on an input
power voltage of a backlight driver.
[0018] In one embodiment, the second circuit comprises an amplifier
including a first terminal electrically connected with the touch
electrode, a second terminal to receive the touch driving signal,
and an output terminal; an integrator circuit configured to output
an integral value of a voltage of the output terminal; and an
analog-to-digital converter configured to convert an output voltage
of the integrator circuit into a digital value, wherein the third
circuit generates the amplitude control signal further based on the
digital value.
[0019] In one embodiment, the second circuit comprises an amplifier
including a first terminal electrically connected with the touch
electrode, a second terminal to receive the touch driving signal,
and an output terminal; a feedback capacitor connected between the
first terminal and the output terminal; an integrator circuit
configured to output an integral value of a voltage of the output
terminal; and an analog-to-digital converter configured to convert
an output voltage of the integrator circuit into a digital value,
wherein the third circuit generates the capacitance control signal
for controlling the capacitance of the feedback capacitor.
[0020] In one embodiment, the second circuit comprises an amplifier
including a first terminal electrically connected with the touch
electrode, a second terminal to receive the touch driving signal,
and an output terminal; an integrator circuit configured to output
an integral value of a voltage of the output terminal; and an
analog-to-digital converter configured to convert an output voltage
of the integrator circuit into a digital value, wherein the third
circuit generates an integrator control signal for controlling a
number of integration times of the integrator circuit.
[0021] In one embodiment, the second circuit comprises an amplifier
including a first terminal electrically connected with the touch
electrode, a second terminal to receive the touch driving signal,
and an output terminal; an integrator circuit configured to output
an integral value of a voltage of the output terminal; and an
analog-to-digital converter configured to convert an output voltage
of the integrator circuit into a digital value, wherein the third
circuit adds a correction value to a sensed value output from the
analog-to-digital converter to generate a corrected sensed value
and generates touch coordinates based on the corrected sensed
value, the correction value generated to have a first value during
the first power mode and a second value during the second power
mode.
[0022] According to an aspect, the present embodiments may provide
a display device that may include: a display panel having a
plurality of touch electrodes embedded therein; a touch circuit
configured to sequentially output touch driving signals for driving
the plurality of touch electrodes; and a touch power integrated
circuit configured to create touch driving signals, which have
different amplitudes depending on the power mode, and supply the
same to the touch circuit.
[0023] According to another aspect, the present embodiments may
provide a touch sensing circuit that may include: a power mode
recognition unit configured to detect the power mode; and a control
unit configured to output an amplitude control signal enabling
creation of touch driving signals that have different amplitudes
depending on the power mode.
[0024] According to still another aspect, the present embodiments
may provide a driving method of a display device, which may
include: recognizing the power mode; creating touch driving signals
that have different amplitudes depending on the detected power
mode; and sequentially applying the touch driving signals to a
plurality of touch electrodes embedded in a display panel.
[0025] According to the present embodiments described above, the
touch drive, which is differentiated according to the power mode,
may be provided in order to thereby improve the touch
sensitivity.
[0026] In addition, according to the present embodiments, when the
power mode corresponds to the battery mode, the degradation of the
touch sensitivity may be prevented.
[0027] Furthermore, according to the present embodiments, when the
power mode is changed, the touch sensitivity may be improved
through an adaptive touch drive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The above and other objects, features, and advantages of the
present invention will be more apparent from the following detailed
description taken in conjunction with the accompanying drawings, in
which:
[0029] FIG. 1 illustrates the overall system configuration of a
display device, according to the present embodiments;
[0030] FIG. 2 and FIG. 3 illustrate the configuration of a touch
system of a display device, according to the present
embodiments;
[0031] FIG. 4 illustrates the power mode and a power system of a
display device, according to the present embodiments;
[0032] FIG. 5 illustrates a touch driving signal that is output
from a touch power integrated circuit and an actual touch driving
signal that is applied to a touch electrode when the power mode
corresponds to an adapter mode and a battery mode, respectively, in
the display device, according to the present embodiments;
[0033] FIG. 6 illustrates a touch driving signal that is output
from a touch power integrated circuit and an actual touch driving
signal that is applied to a touch electrode in cases where a touch
occurs and a touch does not occur, respectively, when the power
mode corresponds to a battery mode in the display device, according
to the present embodiments;
[0034] FIG. 7 is a flowchart showing a driving method for improving
the touch sensitivity of the display device, according to the
present embodiments;
[0035] FIG. 8 is a view to explain the first power mode recognition
method of a micro-control unit in the display device, according to
the present embodiments;
[0036] FIG. 9 is a view to explain the second power mode
recognition method of a micro-control unit in the display device,
according to the present embodiments;
[0037] FIG. 10 is a view to explain an amplitude control method of
a touch driving signal in the display device, according to the
present embodiments;
[0038] FIG. 11 illustrates a touch driving signal that is output
from a touch power integrated circuit and an actual touch driving
signal that is applied to a touch electrode according to the
amplitude control method of the touch driving signal when the power
mode corresponds to an adapter mode and a battery mode,
respectively, in the display device, according to the present
embodiments;
[0039] FIG. 12 illustrates a radical amplitude control method of a
touch driving signal according to the change in the power mode in
the display device, according to the present embodiments;
[0040] FIG. 13a and FIG. 13b illustrate a phased amplitude control
method of a touch driving signal according to the change in the
power mode in the display device, according to the present
embodiments;
[0041] FIG. 14 is a view to explain a feedback capacitor control
method for improving the touch sensitivity in the display device,
according to the present embodiments;
[0042] FIG. 15 is a view to explain an integrator circuit control
method for improving the touch sensitivity in the display device,
according to the present embodiments;
[0043] FIG. 16 is a view to explain a method of correcting a sensed
value for improving the touch sensitivity in the display device,
according to the present embodiments;
[0044] FIG. 17 illustrates a touch power integrated circuit,
according to the present embodiments;
[0045] FIG. 18 illustrates a micro-control unit, according to the
present embodiments;
[0046] FIG. 19 illustrates a touch circuit, according to the
present embodiments; and
[0047] FIG. 20 illustrates a driving integrated circuit, according
to the present embodiments.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0048] Hereinafter, some embodiments of the present invention will
be described in detail with reference to the accompanying
illustrative drawings. In designating elements of the drawings by
reference numerals, the same elements will be designated by the
same reference numerals although they are shown in different
drawings. Further, in the following description of the present
invention, a detailed description of known functions and
configurations incorporated herein will be omitted when it may make
the subject matter of the present invention rather unclear.
[0049] In addition, terms, such as first, second, A, B, (a), (b) or
the like may be used herein when describing components of the
present invention. Each of these terminologies is not used to
define an essence, order or sequence of a corresponding component
but used merely to distinguish the corresponding component from
other component(s). In the case that it is described that a certain
structural element "is connected to", "is coupled to", or "is in
contact with" another structural element, it should be interpreted
that another structural element may "be connected to", "be coupled
to", or "be in contact with" the structural elements as well as
that the certain structural element is directly connected to or is
in direct contact with another structural element.
[0050] FIG. 1 illustrates the overall system configuration of a
display device 100, according to the present embodiments.
[0051] The display device 100, according to the present
embodiments, may provide a display function for displaying images
and a touch sensing function for sensing a user's touch in order to
process inputs.
[0052] Referring to FIG. 1, in order to provide the display
function, the display device, according to the present embodiments,
includes: a display panel 110 on which a plurality of data lines
(DL) and a plurality of gate lines (GL) are arranged and a
plurality of sub-pixels (SP) are arranged; a data driver 120 that
drives the plurality of data lines (DL); a gate driver 130 that
drives the plurality of gate lines (GL); and a controller 140 that
controls the data driver 120 and the gate driver 130.
[0053] The controller 140 supplies various control signals to the
data driver 120 and the gate driver 130 in order to thereby control
the data driver 120 and the gate driver 130.
[0054] The controller 140 starts a scan according to the timing
implemented in each frame, converts input image data, which is
received from the outside, to conform to the data signal format
used in the data driver 120 to then output the converted image
data, and controls the data driver 120 at an appropriate time
according to the scanning.
[0055] The controller 140 may be a timing controller that is
employed in the existing display technology, or may be a control
device that includes the timing controller and further performs
other control functions.
[0056] The controller 140 may be implemented to be integrated with
the data driver 120.
[0057] The data driver 120 supplies a data voltage to the plurality
of data lines (DL) in order to thereby drive the plurality of data
lines (DL). Here, the data driver 120 may be referred to as "source
driver" as well.
[0058] The gate driver 130 sequentially supplies scan signals to
the plurality of gate lines (GL) in order to thereby drive the
plurality of gate lines (GL) in sequence. Here, the gate driver 130
may also be referred to as "scan driver".
[0059] The gate driver 130 sequentially supplies the scan signals
of an on-voltage or an off-voltage to the plurality of gate lines
(GL) under the control of the controller 140.
[0060] When a specific gate line is opened by the gate driver 130,
the data driver 120 converts the image data received from the
controller 140 into a data voltage in the analog form, and then
supplies the same to the plurality of data lines (DL).
[0061] Although the data driver 120 is positioned on only one side
(for example, the upper side or lower side) of the display panel
110 in FIG. 1, the data driver 120 may be positioned on both sides
(for example, the upper and lower sides) of the display panel 110
according to a driving method, a panel design, or the like.
[0062] Although the gate driver 130 is positioned on only one side
(for example, the left side or right side) of the display panel 110
in FIG. 1, the gate driver 130 may be positioned on both sides (for
example, the left and right sides) of the display panel 110
according to a driving method, a panel design, or the like.
[0063] The aforementioned controller 140 receives, from the outside
(for example, a host system), various timing signals including a
vertical synchronization signal (Vsync), a horizontal
synchronization signal (Hsync), an input data enable (DE) signal, a
clock signal (CLK), or the like, as well as the input image
data.
[0064] In addition to the operation of converting the input image
data received from the outside to conform to the data signal format
used in the data driver 120 and outputting the converted image data
in order to control the data driver 120 and the gate driver 130,
the controller 140 receives the timing signals {such as the
vertical synchronization signal (Vsync), the horizontal
synchronization signal (Hsync), the input DE signal, or the clock
signal} and creates various control signals to then be output to
the data driver 120 and the gate driver 130.
[0065] The data driver 120 may include one or more source driver
integrated circuits (SDICs), and may drive the plurality of data
lines.
[0066] Each source driver integrated circuit (SDIC) may be
connected to a bonding pad of the display device 110 in a tape
automated bonding (TAB) type or a chip on glass (COG) type, or may
be directly disposed on the display panel 110, and in some cases,
it may be disposed on the display panel 110 by being integrated. In
addition, each source driver integrated circuit (SDIC) may be
implemented in a chip on film (COF) type in which it is mounted on
a film that is connected to the display panel 110.
[0067] Each source driver integrated circuit (SDIC) may include a
shift register, a latch circuit, a digital-to-analog converter
(DAC), an output buffer, and the like.
[0068] The gate driver 130 may include one or more gate driver
integrated circuits (GDICs).
[0069] Each gate driver integrated circuit (GDIC) may be connected
to a bonding pad of the display device 110 in a tape automated
bonding (TAB) type or a chip on glass (COG) type, or may be
directly disposed on the display panel 110 by being implemented in
a gate in panel (GIP) type, and in some cases, it may be disposed
on the display panel 110 by being integrated. In addition, each
gate driver integrated circuit (GDIC) may be implemented in a chip
on film (COF) type in which it is mounted on a film that is
connected to the display panel 110.
[0070] Each gate driver integrated circuit (GDIC) may include a
shift register, a level shifter, and the like.
[0071] The display device 100, according to the present
embodiments, may include one or more source printed circuit boards
(S-PCBs) that are necessary for the circuit connection with respect
to one or more source driver integrated circuits (SDICs) and a
control printed circuit board (C-PCB) for mounting control
components and various electrical devices.
[0072] A film, on which the source driver integrated circuit (SDIC)
is mounted, may be connected between one or more source printed
circuit boards (S-PCBs) and the display panel 110.
[0073] The controller 140, which controls the operation of the data
driver 120 and the gate driver 130, and a power controller, which
supplies various voltages or currents to the display panel 110, the
data driver 120, and the gate driver 130, or controls the various
voltages or currents to be supplied, may be mounted on the control
printed circuit board (C-PCB).
[0074] One or more source printed circuit boards (S-PCB) and the
control printed circuit board (C-PCB) may be connected with each
other through a connection medium, such as a flexible printed
circuit (FPC) or a flexible flat cable (FFC).
[0075] One or more source printed circuit boards (S-PCB) and the
control printed circuit board (C-PCB) may be implemented to be
integrated in a single printed circuit board.
[0076] The display device 100, according to the present
embodiments, may be various types of devices, such as a liquid
crystal display device, an organic light emitting display device, a
plasma display device, or the like.
[0077] In addition, the display device 100, according to the
present embodiment, for example, may be a mobile device, such as
laptop computers, tablets, or smart phones. Furthermore, any device
may be adopted, which has the display panel 110 and two or more
power sources as the power supply means.
[0078] FIG. 2 and FIG. 3 illustrate the configuration of a touch
system 200 of the display device 100, according to the present
embodiments.
[0079] Referring to FIG. 2, the display device 100, according to
the present embodiments, includes the touch system 200 to provide a
touch sensing function.
[0080] Referring to FIG. 2, the touch system 200 may include at
least one of: a plurality of touch electrodes (TE); a touch circuit
210; a micro-control unit 220; or a touch power IC (TPIC) 230. This
touch system 220 may be referred to as a touch sensing circuit or a
touch driving circuit as well.
[0081] The plurality of touch electrodes (TE) serve as a touch
sensor.
[0082] The touch power integrated circuit 230 creates touch driving
signals (TDS) at an output port of the touch power integrated
circuit 230. The touch driving signals (TDS) are for driving the
plurality of touch electrodes (TE) to then be supplied to the touch
circuit 210.
[0083] Here, the touch driving signal (TDS) may be a pulse width
modulation signal in which a high level voltage and a low level
voltage alternate with each other according to a predetermined duty
cycle. Accordingly, the touch driving signal (TDS) may have a
controlled phase and amplitude.
[0084] The touch circuit 210 has an input port that is coupled to
an output port of the touch power IC 230. The touch circuit 210
receives the touch driving signal TDS from the output port of the
touch power IC 230 and sequentially applies the touch driving
signals (TDS) supplied from the touch power integrated circuit 230
to the plurality of touch electrodes (TE) in order to thereby drive
the plurality of touch electrodes (TE) in sequence.
[0085] In addition, the touch circuit 210 receives a touch sensing
signal (TSS) from the touch electrode (TE), to which the touch
driving signal (TDS) has been applied, and supplies the
micro-control unit 220a with a sensed touch value (sensed touch
data) corresponding to a digital value based on the received touch
sensing signal (TSS).
[0086] The micro-control unit 220 may detect whether or not the
touch has been made based on the sensed touch value received from
the touch circuit 210, and may calculate the coordinates of the
touch.
[0087] Referring to FIG. 3, the plurality of touch electrodes (TE)
may be disposed to be embedded in the display panel 110. Thus, the
display device 100, according to the present embodiments, may have
the embedded type of touch structure, such as an in-cell type or an
on-cell type.
[0088] The plurality of touch electrodes (TE) disposed on the
display panel 110 may be electrodes that are dedicated to a touch
mode for the touch sensing.
[0089] Alternatively, the plurality of touch electrodes (TE)
disposed on the display panel 110 may be mode common electrodes to
which a voltage necessary for the display drive is applied in a
display mode and the touch driving signal (TDS) is applied in a
touch mode.
[0090] For example, the plurality of touch electrodes (TE) disposed
on the display panel 110 may be common electrodes to which a common
voltage (Vcom) corresponding to a pixel voltage of each sub-pixel
is applied in the display mode.
[0091] Referring to FIG. 3, each of the plurality of touch
electrodes (TE) disposed on the display panel 110 may be connected
with a signal line (SL).
[0092] The touch circuit 210 may output the touch driving signal
(TDS) to one of a plurality of signal lines (SL) in order to
thereby drive one of the plurality of touch electrodes (TE).
[0093] Referring to FIG. 3, the touch circuit 210 may include an
amplifier 310, an integrator circuit 320, an analog-to-digital
converter 330, a feedback capacitor (Cfb), and a multiplexer
(MUX).
[0094] The amplifier 310 is comprised of: the first terminal (n1)
that is electrically connected with the touch electrode (TE); the
second terminal (n2) to which the touch driving signal (TDS) is
applied; and an output terminal (n3) that outputs the touch sensing
signal (TSS).
[0095] The feedback capacitor (Cfb) is connected between the first
terminal (n1) and the output terminal (n3) of the amplifier
310.
[0096] The feedback capacitor (Cfb) may be a fixed capacitor that
has a fixed capacitance, or may be a variable capacitor that has a
variable capacitance.
[0097] In addition, the feedback capacitor (Cfb) may be comprised
of a plurality of capacitors. In the case where the feedback
capacitor (Cfb) is the variable capacitor, it may be comprised of a
plurality of capacitors and a plurality of switches.
[0098] The integrator circuit 320 outputs an integral value of the
output voltage of the amplifier 310 {that is, the touch sensing
signal that is output from the output terminal (n3) of the
amplifier 310}. Such an integrator circuit 320 may be comprised of
devices, such as comparators or capacitors.
[0099] The analog-to-digital converter (ADC) 330 converts the
output voltage (the integral value) of the integrator circuit 320
into a digital value, and outputs the same as a sensed touch
value.
[0100] The multiplexer (MUX) may output the touch driving signal
(TDS) to the signal lines (SL) that are connected with the touch
electrodes (TE) to be driven among the plurality of sensing lines
(SL).
[0101] Meanwhile, the touch sensing circuit for the touch sensing
may include, in the form of an integrated circuit, at least one of:
the touch circuit 210; the micro-control unit 220; or the touch
power integrated circuit 230.
[0102] In this regard, the touch circuit 210, the micro-control
unit 220, and the touch power integrated circuit 230 may be
implemented as separate integrated circuits, respectively.
[0103] In some cases, the touch sensing circuit may be an
integrated circuit that includes the touch circuit 210 and the
micro-control unit 220.
[0104] Alternatively, the touch sensing circuit may be an
integrated circuit that includes the touch circuit 210, the
micro-control unit 220, and the touch power integrated circuit
230.
[0105] FIG. 4 illustrates the power mode (PM) and a power system
410 of the display device 100, according to the present
embodiments. In the following description, it is assumed that the
display device 100, according to the present embodiments, is a
liquid crystal display device that includes a backlight unit
(BLU).
[0106] Referring to FIG. 4, the display device 100, according to
the present embodiments, adopts a battery 411 and an power adapter
412 in order to thereby operate by using a power voltage (Va)
supplied through the adapter 412, or by using a power voltage (Vb)
supplied from the battery 411. For example, the adapter 412 can be
an AC-DC adapter that converts an AC voltage into a DC power
voltage (Va).
[0107] Thus, the power mode (PM) of the display device 100,
according to the present embodiments, has an adapter mode (AM) for
using the power voltage (Va) supplied through the adapter 412 and a
battery mode (BM) for using the power voltage (Vb) supplied from
the battery 411.
[0108] Referring to FIG. 4, the display device 100, according to
the present embodiments, includes a power system 410 that manages
the power mode (PM) and supplies the power necessary for the
operations of various elements in the display device 100.
[0109] The power system 410 of the display device 100, according to
the present embodiments, may include: a battery 411 as a power
source; an adapter 412 as power supply means; the first diode (D1)
that allows the power voltage (Vb) supplied from the battery 411 to
be fed only in the forward direction; the second diode (D2) that
allows the power voltage (Va) supplied from the adapter 412 to be
fed only in the forward direction; and a buck circuit 413 that
receives the voltage (Va or Vb) at the point Px where the output
terminals of the first diode (D1) and the second diode (D2) are
connected with each other and converts the same into the VCC input
voltage (for example, 3.3V) necessary for driving the display panel
110 to then output the same.
[0110] Although the power voltage (Vb) may be supplied from the
battery 411, when the power voltage (Va) is input through the
adapter 412, the above-mentioned buck circuit 413 converts the
power voltage (Va) supplied through the adapter 412 into the VCC
input voltage (for example, 3.3V) necessary for driving the display
panel 110 to then output the same.
[0111] In addition, when the power voltage (Va) is not supplied
through the adapter 412, the buck circuit 413 converts the power
voltage (Vb) supplied from the battery 411 into the VCC input
voltage (for example, 3.3V) necessary for driving the display panel
110 to then output the same.
[0112] The VCC input voltage output from the buck circuit 413 is
supplied to the source printed circuit board 430 through a flexible
flat cable 420.
[0113] In addition, for example, the source driver integrated
circuit 450, which is implemented in the chip on film (COF) type,
is mounted on a film 440, and the ends of the film 440 having the
source driver integrated circuit 450 mounted thereon are bonded to
the printed circuit board 430 and the display panel 110,
respectively.
[0114] Thus, the VCC input voltage output from the buck circuit 413
may be supplied to the film 440 and the source driver integrated
circuit 450 mounted thereon through the flexible flat cable 420 and
the source printed circuit board 430.
[0115] As described above, the voltage at the node Px may
correspond to the power voltage (Va) supplied through the adapter
412 or the power voltage (Vb) supplied from the battery 411
according to whether or not the power is supplied through the
adapter 412.
[0116] The voltage (Va or Vb) at the node Px is used as a voltage
for the input power of a backlight driver (not shown), which is
applied to the backlight driver.
[0117] Accordingly, it may be determined whether the power mode
(PM) corresponds to the battery mode (BM) or the adapter mode (AM)
by identifying the input power voltage value of the backlight
driver.
[0118] Meanwhile, the power voltage (Va) supplied through the
adapter 412 may not be the same as the power voltage (Vb) supplied
from the battery 411.
[0119] In general, the power voltage (Vb) supplied from the battery
411 is lower than the power voltage (Va) supplied through the
adapter 412. For example, the power voltage (Vb) supplied from the
battery 411 may be 12V, and the power voltage (Va) supplied through
the adapter 412 may be 19V.
[0120] Due to the discrepancy between the power voltage (Va)
supplied through the adapter 412 and the power voltage (Vb)
supplied from the battery 411, the touch driving performance in the
battery mode (BM) may be different from the touch driving
performance in the adapter mode (AM), and the touch sensitivity in
the battery mode (BM) may be different from the touch sensitivity
in the adapter mode (AM).
[0121] Meanwhile, in particular, when the power mode (PM)
corresponds to the battery mode (BM), deviations of the touch
driving performance and the touch sensitivity may occur between the
case where the touch occurs and the case where the touch does not
occur.
[0122] The phenomenon, in which the touch sensitivity deviation
occurs depending on the power mode (PM) {in particular, the
degradation of the touch sensitivity in the battery mode (BM)}, and
the phenomenon, in which the touch sensitivity deviation occurs
depending on whether or not the touch is made {in particular, the
degradation of the touch sensitivity in the battery mode (BM) upon
the occurrence of the touch}, will be described with reference to
FIG. 5 and FIG. 6.
[0123] FIG. 5 illustrates the touch driving signal (TDS) that is
output from the touch power integrated circuit (TPIC) 230 and the
actual touch driving signal (TDS) that is applied to the touch
electrode (TE) when the power mode (PM) corresponds to the adapter
mode (AM) and the battery mode (BM), respectively, in the display
device 100, according to the present embodiments.
[0124] FIG. 5 is a view to explain the phenomenon in which the
touch sensitivity deviation depending on the power mode (PM) {in
particular, the degradation of the touch sensitivity in the battery
mode (BM)} occurs.
[0125] Referring to FIG. 5, regardless of the type of power mode
(PM), the touch power integrated circuit 230 may supply the touch
driving signals (TDS), which have the same amplitude (.DELTA.V) at
the output port of the touch power integrated circuit 230, to the
touch circuit 210.
[0126] Referring to FIG. 5, although the touch power integrated
circuit 230 outputs the touch driving signals (TDS) that have the
same amplitude (.DELTA.V) in the adapter mode (AM) and in the
battery mode (BM), the amplitudes of the actual touch driving
signals (TDS), which are applied to the touch electrodes (TE) of
the display panel 110 through the touch circuit 210, may be
different from each other.
[0127] In the adapter mode (AM), the amplitude of the actual touch
driving signal (TDS) applied to the touch electrode (TE) is almost
the same as, or a little bit lower than, the amplitude (.DELTA.V)
of the touch driving signal (TDS) that is output from the touch
power integrated circuit 230.
[0128] On the contrary, in the battery mode (BM), the amplitude of
the actual touch driving signal (TDS) applied to the touch
electrode (TE) may become low enough to give influence to the touch
sensitivity, compared with the amplitude (.DELTA.V) of the touch
driving signal (TDS) that is output from the touch power integrated
circuit 230.
[0129] Therefore, such reduction in the amplitude of the touch
driving signal (TDS) in the battery mode (BM) causes the touch
sensitivity to deteriorate in the battery mode (BM).
[0130] FIG. 6 illustrates the touch driving signal (TDS) that is
output from the touch power integrated circuit 230 and the actual
touch driving signal (TDS) that is applied to the touch electrode
(TE) in cases where a touch occurs and a touch does not occur,
respectively, when the power mode (PM) corresponds to the battery
mode (BM) in the display device 100, according to the present
embodiments.
[0131] FIG. 6 is a view to explain the phenomenon in which the
touch sensitivity deviation depending on the occurrence of the
touch {in particular, the degradation of the touch sensitivity upon
the occurrence of the touch in the battery mode (BM)} occurs.
[0132] Referring to FIG. 6, regardless of the occurrence of the
touch, the touch power integrated circuit 230 supplies the touch
driving signals (TDS), which have the same amplitude (.DELTA.V), to
the touch circuit 210.
[0133] Referring to FIG. 6, although the touch power integrated
circuit 230 outputs the touch driving signals (TDS) that have the
same amplitude (.DELTA.V) when the touch occurs and when the touch
does not occur, the amplitudes of the actual touch driving signals
(TDS) applied to the touch electrodes (TE) of the display panel 110
through the touch circuit 210 may be different from each other.
[0134] The amount of reduction in the amplitude of the actual touch
driving signal (TDS) applied to the touch electrode (TE) when the
touch occurs, with respect to the amplitude (.DELTA.V) of the touch
driving signal (TDS) that is output from the touch power integrated
circuit 230, is big enough to degrade the touch sensitivity
{compared to the amount of reduction in the amplitude of the actual
touch driving signal (TDS) applied to the touch electrode (TE),
when the touch does not occur, with respect to the amplitude
(.DELTA.V) of the touch driving signal (TDS) that is output from
the touch power integrated circuit 230}.
[0135] As described above, as the amount of reduction in the
amplitude upon the occurrence of the touch increases, the touch
sensitivity deteriorates. This phenomenon mainly occurs in the
battery mode (BM).
[0136] Therefore, the present embodiments disclose a touch
sensitivity improving method for preventing the degradation of the
touch sensitivity in the battery mode (BM) and preventing the
degradation of the touch sensitivity upon the occurrence of the
touch, and further discloses the display device 100, the touch
system 200, the touch circuit 210, the micro-control unit 220, and
the touch power integrated circuit (TPIC) 430 for the same.
[0137] Hereinafter, the driving method for the touch sensitivity
improvement of the display device 100, according to the present
embodiments, will be briefly described first, and then, the display
device 100, the touch system 200, the touch circuit 210, the
micro-control unit 220, and the touch power integrated circuit
(TPIC) 430 for providing the driving method for the touch
sensitivity improvement will be described.
[0138] FIG. 7 is a flowchart showing the driving method for
improving the touch sensitivity of the display device 100,
according to the present embodiments.
[0139] Referring to FIG. 7, the display device 100, according to
the present embodiments, provides a driving method for improving
the touch sensitivity, and the driving method may include:
recognizing the power mode (PM) (S710); creating the touch driving
signals (TDS) that have different amplitudes at output ports of the
touch driving IC according to the detected power mode (PM), which
is an operation of controlling the amplitude of the touch driving
signal (TDS) (S720); and sequentially applying the touch driving
signals (TDS) to a plurality of touch electrodes (TE) embedded in
the display panel 110 (S730).
[0140] The touch system 200 of the display device 100, which
provides the driving method for the touch sensitivity improvement
as described above, includes the touch circuit 210 that
sequentially outputs the touch driving signals (TDS) for driving
the plurality of touch electrodes (TE) embedded in the display
panel 110, and the touch power integrated circuit 230 that creates
the touch driving signals (TDS), which have different amplitudes
according to the power mode (PM), and supplies the same to the
touch circuit 210.
[0141] According to the description above, the touch driving
signals (TDS) having different amplitudes at the output port of the
touch power integrated circuit 230 are intentionally created
depending on the power mode (PM) and are used for the touch drive,
so that the reduction in the amplitude of the touch driving signal
(TDS) or the deviation of the reduction amount of the amplitude
depending on the power mode (PM) may be prevented, and accordingly,
the degradation of the touch sensitivity or the touch sensitivity
deviation depending on the power mode (PM) may be prevented in
order to thereby improve the touch sensitivity.
[0142] As described above, the amplitude of the touch driving
signal (TDS) at the output port of the touch power integrated
circuit 230 is different according to the power mode (PM).
[0143] For example, at the output port of the touch power
integrated circuit 230, the amplitude (.DELTA.Vbc) of the touch
driving signal (TDS) that is created in the battery mode (BM) may
be greater than the amplitude (.DELTA.Vac) of the touch driving
signal (TDS) that is created in the adapter mode (AM). As a result,
.DELTA.Vbc and .DELTA.Vac are different from each other. Amplitude
as used herein may refer to the peak to peak amplitude of a
signal.
[0144] Here, the difference between the amplitude (.DELTA.Vbc) of
the touch driving signal (TDS) that is created in the battery mode
(BM) and the amplitude (.DELTA.Vac) of the touch driving signal
(TDS) that is created in the adapter mode (AM), by the touch power
integrated circuit 230, may be configured according to the
difference between the amount of reduction in the amplitude of the
touch driving signal (TDS) in the battery mode (BM) and the amount
of reduction in the amplitude of the touch driving signal (TDS) in
the adapter mode (AM).
[0145] Since the amount of reduction in the amplitude in the
battery mode (BM) is greater, the amplitude of the actual touch
driving signal (TDS) applied to the touch electrode (TE) in both
the battery mode (BM) and the adapter mode (AM) may be the same
.DELTA.Vt by configuring the amplitude (.DELTA.Vbc) of the touch
driving signal (TDS) that is created in the battery mode (BM) to be
greater than the amplitude (.DELTA.Vac) of the touch driving signal
(TDS) that is created in the adapter mode (AM).
[0146] Meanwhile, since there is little or no reduction in the
amplitude of the touch driving signal (TDS) when the power mode
(PM) corresponds to the adapter mode (AM), the amplitude
(.DELTA.Vac) of the touch driving signal (TDS) that is created in
the adapter mode (AM) may be considered to be almost the same as
the amplitude (.DELTA.Vt) of the actual touch driving signal (TDS)
that is applied to the touch electrode (TE).
[0147] Hereinafter, the amplitude (.DELTA.Vt) of the actual touch
driving signal (TDS) applied to the touch electrode (TE) will be
expressed as .DELTA.Vt, which may be the targeted amplitude in the
case where the touch driving signal (TDS) is created in the adapter
mode (AM) and the battery mode (BM), respectively, and may be
almost the same as the amplitude (.DELTA.Vac) of the touch driving
signal (TDS) that is created in the adapter mode (AM).
[0148] As described above, the difference between the amplitude of
the actual touch driving signal (TDS) applied to the touch
electrode (TE) in the adapter mode (AM) and the amplitude of the
actual touch driving signal (TDS) applied to the touch electrode
(TE) in the battery mode (BM), may be reduced by generating the
touch driving signal (TDS) that has the greater amplitude
(.DELTA.Vbc) in the battery mode (BM) than that in the adapter mode
(AM) when the touch power integrated circuit 230 generates the
touch driving signals (TDS).
[0149] In particular, in order to compensate for the reduction in
the amplitude of the touch driving signal (TDS), which is generated
in the course of transmitting the touch driving signal (TDS) in the
battery mode (BM), the touch driving signal (TDS) is generated
through amplitude control so that the touch driving signal (TDS),
which does not cause the reduction in the touch sensitivity, may be
applied to the touch electrode (TE). According to this, the touch
sensitivity may be improved in the battery mode (BM).
[0150] Meanwhile, the touch power integrated circuit 230 may create
the touch driving signals (TDS) that have different amplitudes
depending on the input power voltage (VLED) of the backlight
driver.
[0151] For example, if the input power voltage (VLED) of the
backlight driver corresponds to the power voltage (Va) that is
supplied through the adapter 412, the touch power integrated
circuit 230 may create the touch driving signal (TDS) that has an
amplitude (.DELTA.Vac) corresponding to the adapter mode (AM), and
if the input power voltage (VLED) of the backlight driver
corresponds to the power voltage (Vb) that is supplied from the
battery 411, the touch power integrated circuit 230 may create the
touch driving signal (TDS) that has an amplitude (.DELTA.Vbc)
corresponding to the battery mode (BM).
[0152] As described with reference to FIG. 4 above, when the input
power voltage (VLED) of the backlight driver is identified, the
power mode (PM) may be detected to be either the battery mode (BM)
or the adapter mode (AM). Therefore, the touch power integrated
circuit 230 may perform the amplitude control of the touch driving
signal (TDS) based on the input power voltage (VLED) of the
backlight driver.
[0153] Meanwhile, when the power mode (PM) is changed
(AM.fwdarw.BM, BM.fwdarw.AM), the touch power integrated circuit
230 may perform the amplitude control in which the amplitude of the
touch driving signal (TDS) is changed step by step, and may supply
the touch circuit 210 with the touch driving signal (TDS) having
the amplitude that has been controlled step by step.
[0154] More specifically, when the power mode (PM) switches from
the adapter mode (AM) to the battery mode (BM), the touch power
integrated circuit 230 increases the amplitude (.DELTA.Vac) of the
touch driving signal (TDS) in the adapter mode (AM) to the
amplitude (.DELTA.Vbc) corresponding to the battery mode (BM) step
by step through one or more intermediate increased amplitudes
(.DELTA.Vi), and supplies the touch driving signal (TDS) having the
controlled amplitude (.DELTA.V) to the touch circuit 210 in each
step.
[0155] When the power mode (PM) switches from the battery mode (BM)
to the adapter mode (AM), the touch power integrated circuit 230
reduces the amplitude (.DELTA.Vbc) of the touch driving signal
(TDS) in the battery mode (BM) to the amplitude (.DELTA.Vac)
corresponding to the adapter mode (AM) step by step through one or
more intermediate reduced amplitudes (.DELTA.Vd), and supplies the
touch driving signal (TDS) having the controlled amplitude
(.DELTA.V) to the touch circuit 210 in each step.
[0156] As described above, when the power mode is changed, the
sensing instability due to a sudden fluctuation of the amplitude of
the touch driving signal (TDS) may be attenuated through the phased
change in the amplitude.
[0157] For the amplitude control mentioned above, the micro-control
unit 220 may detect the power mode (PM), and may output an
amplitude control signal (ACS) to the touch power integrated
circuit 230.
[0158] Accordingly, the touch power integrated circuit 230 controls
the amplitude (.DELTA.V) based on the amplitude control signal
(ACS) received from the micro-control unit 220, and creates the
touch driving signal (TDS) having the controlled amplitude
(.DELTA.V) to then be supplied to the touch circuit 210.
[0159] As described above, the micro-control unit 220 may provide
the touch power integrated circuit 230 with the amplitude control
signal for controlling the amplitude of the touch driving signal
(TDS) so that the touch power integrated circuit 230 can accurately
and efficiently control the amplitude of the touch driving signal
(TDS).
[0160] Hereinafter, the power mode recognition method and the
amplitude control method for improving the touch sensitivity will
be described in more detail, respectively.
[0161] FIG. 8 is a view to explain the first power mode recognition
method of the micro-control unit 220 in the display device 100,
according to the present embodiments.
[0162] Referring to FIG. 8, the micro-control unit 220 may detect
whether the power mode (PM) is the adapter mode (AM) or the battery
mode (BM) based on the input power voltage (VLED) of the backlight
driver.
[0163] As described above, the power mode (PM) may be easily and
accurately detected by using the input power of the backlight
driver.
[0164] To this end, the micro-control unit 220 may include a
comparator 800 that receives the input power voltage (VLED) of the
backlight driver and a reference voltage (VREF) and outputs a
comparison result signal, and may detect the power mode (PM) to be
one of the adapter mode (AM) or the battery mode (BM) based on the
comparison result signal (High or Low) of the comparator 800.
[0165] As described above, the comparator 800 may receive the input
power voltage (VLED) of the backlight driver and the reference
voltage (VREF), and may compare the input power voltage (VLED) of
the backlight driver with the reference voltage (VREF) in order to
thereby output the comparison result signal.
[0166] Alternatively, the comparator 800 may receive a voltage
(Scaled VLED), which is obtained by scaling the input power voltage
(VLED) of the backlight driver by using a voltage dividing circuit,
and the reference voltage (VREF), and may compare the scaled input
power voltage (Scaled VIED) of the backlight driver with the
reference voltage (VREF) in order to thereby output the comparison
result signal.
[0167] Here, the voltage dividing circuit may include two or more
resistors (R1 and R2), and in some cases, the voltage dividing
circuit may further include one or more capacitors (C2).
[0168] The voltage dividing circuit shown in FIG. 8 is configured
by the first resistor (R1) and the second resistor (R2), which are
connected with each other in series between the input power voltage
(VLED) of the backlight driver and the ground voltage, wherein the
connection point between the first resistor (R1) and the second
resistor (R2) is connected to the positive input terminal of the
comparator 800.
[0169] The connection point between the first resistor (R1) and the
second resistor (R2) has the scaled input power voltage (Scaled
VIED) of the backlight driver.
[0170] The input power voltage (VLED) of the backlight driver
corresponds to the power voltage (Va) supplied through the adapter
412 in the adapter mode (AM), and the input power voltage (VLED) of
the backlight driver corresponds to the power voltage (Vb) supplied
from the battery 411 in the battery mode (BM).
[0171] Since the power voltage (Vb) supplied from the battery 411
is lower than the power voltage (Va) supplied through the adapter
412, the voltage to be applied to the positive input terminal of
the comparator 800 becomes low in the battery mode (BM), and the
voltage to be applied to the positive input terminal of the
comparator 800 becomes high in the adapter mode (AM).
[0172] The reference voltage may correspond to the voltage between
the voltage to be applied to the positive input terminal of the
comparator 800 in the battery mode (BM) and the voltage to be
applied to the positive input terminal of the comparator 800 in the
adapter mode (AM).
[0173] If the comparison result signal of the comparator 800 is a
high level signal, the micro-control unit 220 detect the power mode
(PM) to be the adapter mode (AM).
[0174] If the comparison result signal of the comparator 800 is a
low level signal, the micro-control unit 220 detect the power mode
(PM) to be the battery mode (BM).
[0175] FIG. 9 is a view to explain the second power mode
recognition method of the micro-control unit 220 in the display
device 100, according to the present embodiments.
[0176] Referring to FIG. 9, the micro control unit 220 may receive
power mode (PM) information from the power system 410 in order to
thereby detect the power mode (PM) to be one of the adapter mode
(AM) or the battery mode (BM).
[0177] Here, the power system 410 may perform the power mode
recognition in the same manner as the power mode recognition method
of the micro-control unit 220 described with reference to FIG.
8.
[0178] FIG. 10 is a view to explain the amplitude control method of
the touch driving signal (TDS) in the display device 100, according
to the present embodiments, and FIG. 11 illustrates the touch
driving signal (TDS) that is output from the touch power integrated
circuit 230 and the actual touch driving signal (TDS) that is
applied to the touch electrode (TE) according to the amplitude
control method of the touch driving signal (TDS) when the power
mode (PM) corresponds to the adapter mode (AM) and the battery mode
(BM), respectively, in the display device 100, according to the
present embodiments
[0179] The MCU 220 detects the power mode and then generates an
amplitude control signal ACS based on whether the detected power
mode is battery mode (BM) or adapter mode (AM).
[0180] Referring to FIG. 10, if the power mode (PM) is detected to
be the battery mode (BM) as a result of the power mode recognition,
the micro-control unit 220 may output an amplitude control signal
(ACS) to the touch power integrated circuit 230.
[0181] Here, the amplitude control signal, which is output when the
power mode (PM) is detected to be the battery mode (BM), may
contain at least one piece of the power mode information, which
states that the power mode (PM) corresponds to the battery mode
(BM), or includes information about an amount of amplitude
increase.
[0182] Accordingly, the touch power integrated circuit 230 may
create the touch driving signal (TDS), which has a pre-defined
amplitude (.DELTA.Vbc) in the battery mode (BM), according to the
power mode information contained in the amplitude control signal,
and may output the same.
[0183] Alternatively, the touch power integrated circuit 230 may
create the touch driving signal (TDS), which has an amplitude
(.DELTA.Vbc) that is controlled according to the
amplitude-increased amount information contained in the amplitude
control signal, and may output the same.
[0184] As described above, the micro-control unit 220 may provide
the touch power integrated circuit 230 with the amplitude control
signal (ACS) for controlling the amplitude of the touch driving
signal (TDS) through the power mode recognition so that the touch
power integrated circuit 230 may accurately and efficiently control
the amplitude of the touch driving signal (TDS) according to the
amplitude control signal (ACS).
[0185] Meanwhile, if the power mode (PM) is detected to be the
adapter mode (AM) as a result of the power mode recognition, the
micro-control unit 220 may not output the amplitude control signal
(ACS) to the touch power integrated circuit 230.
[0186] That is, the micro-control unit 220 may output the amplitude
control signal (ACS) to the touch power integrated circuit 230 only
when the power mode (PM) is identified to be the battery mode (BM)
as a result of the power mode recognition.
[0187] Alternatively, due to the power mode change, the
micro-control unit 220 needs to create the amplitude control signal
(ACS) corresponding to the adapter mode (AM) and needs to output
the same to the touch power integrated circuit 230 even when the
power mode (PM) is identified to be the adapter mode (AM).
[0188] Therefore, with the extension or generalization of the
function in consideration of the power mode changing situation, if
the power mode (PM) switches from the adapter mode (AM) to the
battery mode (BM) as a result of the power mode recognition, the
micro-control unit 220 creates and outputs the amplitude control
signal (ACS) that contains at least one of the power mode
information (power mode change information), which states that the
power mode (PM) has switched from the adapter mode (AM) to the
battery mode (BM), or the amplitude-increased amount
information.
[0189] In addition, if the power mode (PM) switches from the
battery mode (BM) to the adapter mode (AM) as a result of the power
mode recognition, the micro-control unit 220 creates and outputs
the amplitude control signal (ACS) that contains at least one of
the power mode information (power mode change information), which
states that the power mode (PM) has switched from the battery mode
(BM) to the adapter mode (AM), or the amplitude-increased amount
information.
[0190] Meanwhile, the micro-control unit 220 may determine the
amplitude-increased amount information or the amplitude-reduced
amount information, which may be contained in the amplitude control
signal (ACS), based on the result of recognizing the power mode
(PM) and a touch sensing signal (TSS) that is received through the
touch electrode (TE) to which the touch driving signal (TDS) is
applied (i.e. based on a sensed value corresponding to a digital
value of the touch sensing signal (TSS)).
[0191] This is intended to detect whether or not the amplitude of
the actual touch driving signal (TDS) applied to the touch
electrode (TE) reaches a desired amplitude (.DELTA.Vt) as a result
of amplitude control, through the touch sensing signal (TSS), in
order to thereby re-adjust the amplitude control signal ACS until
the amplitude of the actual touch driving signal (TDS) applied to
the touch electrode (TE) reaches the desired amplitude (.DELTA.Vt).
According to this, it is possible to make an accurate amplitude
control so that the touch sensitivity may be further improved.
[0192] Referring to FIG. 11, according to the amplitude control
above, when the power mode (PM) corresponds to the battery mode
(BM), the touch power integrated circuit 230 controls the amplitude
(.DELTA.Vbc) of the touch driving signal (TDS) at the output port
of the touch power integrated circuit 230 to be greater than the
amplitude (.DELTA.Vt) of the actual touch driving signal (TDS) that
is desired to be applied to the touch electrode (TE). This accounts
for the reduction in the amplitude. Accordingly, even with the
reduction in the amplitude, the actual touch driving signal (TDS)
applied to the touch electrode (TE) may have the desired amplitude
(.DELTA.Vt).
[0193] Meanwhile, provided that there is no reduction in the
amplitude in the adapter mode (AM), the touch power integrated
circuit 230 may create and output the touch driving signal (TDS)
that has the same amplitude (.DELTA.Vac) as the amplitude
(.DELTA.Vt) of the actual touch driving signal (TDS) that is
desired to be applied to the touch electrode (TE) without the
amplitude control.
[0194] Provided that there is a slight reduction in the amplitude
in the adapter mode (AM), the touch power integrated circuit 230
may create and output the touch driving signal (TDS) having the
amplitude (.DELTA.Vac) at the output port of the touch power
integrated circuit 230 that is greater than the amplitude
(.DELTA.Vt) of the actual touch driving signal (TDS), which is
desired to be applied to the touch electrode (TE), by the amount of
reduction in the amplitude.
[0195] Hereinafter, two amplitude control methods for the touch
driving signal (TDS) in the case of the change in the power mode
will be described.
[0196] FIG. 12 illustrates a radical amplitude control method of
the touch driving signal (TDS) according to the change in the power
mode in the display device 100, according to the present
embodiments.
[0197] Referring to FIG. 12, a single frame may be divided into a
touch mode period and a display mode period.
[0198] Provided that the touch electrode (TE) is the mode common
electrode, the touch driving signals (TDS) are sequentially applied
to the touch electrodes (TE) in the touch mode period, and the
common voltage (Vcom) may be applied to all of the touch electrodes
(TE) in the display mode period.
[0199] Referring to FIG. 12, when the frame 1 switches to the frame
2, the adapter mode (AM) switches to the battery mode (BM).
[0200] In the touch mode period of the frame 1 in which the power
mode (PM) corresponds to the adapter mode (AM), the amplitude of
the touch driving signal (TDS), which is output from the touch
power integrated circuit 230, is .DELTA.Vac corresponding to the
adapter mode (AM).
[0201] In addition, in the touch mode period of the frame 2 in
which the power mode (PM) switches to the battery mode (BM), the
touch power integrated circuit 230 creates and outputs the touch
driving signal (TDS) that has an amplitude (.DELTA.Vbc)
corresponding to the battery mode (BM) through the amplitude
control.
[0202] Here, the amplitude (.DELTA.Vbc) corresponding to the
battery mode (BM) is greater than the amplitude (.DELTA.Vac)
corresponding to the adapter mode (AM).
[0203] Referring to FIG. 12, when the frame 3 switches to the frame
4, the battery mode (BM) switches to the adapter mode (AM).
[0204] In the touch mode period of the frame 3 in which the power
mode (PM) corresponds to the battery mode (BM), the amplitude of
the touch driving signal (TDS), which is output from the touch
power integrated circuit 230, is .DELTA.Vbc corresponding to the
battery mode (BM).
[0205] In addition, in the touch mode period of the frame 4 in
which the power mode (PM) switches to the adapter mode (AM), the
touch power integrated circuit 230 creates and outputs the touch
driving signal (TDS) that has an amplitude (.DELTA.Vac)
corresponding to the adapter mode (AM) through the amplitude
control.
[0206] Here, the amplitude (.DELTA.Vac) corresponding to the
adapter mode (AM) is smaller than the amplitude (.DELTA.Vbc)
corresponding to the battery mode (BM).
[0207] Referring to FIG. 12, when the power mode is changed, the
amplitude (.DELTA.Vac) corresponding to the adapter mode (AM)
before the change is directly changed to the amplitude (.DELTA.Vbc)
corresponding to the changed battery mode (BM). In addition, the
amplitude (.DELTA.Vbc) corresponding to the previous battery mode
(BM) is directly changed to the amplitude (.DELTA.Vac)
corresponding to the changed adapter mode (AM).
[0208] According to the description above, the amplitude control
method shown in FIG. 12 refers to an fast amplitude control method
in which the amplitude corresponding to the previous power mode is
directly changed to the amplitude corresponding to the changed
power mode when changing the amplitude according to the change in
the power mode.
[0209] Hereinafter, a phased amplitude control method will be
described, in which the amplitude corresponding to the previous
power mode is changed to the intermediate amplitude more than once,
and then is changed to the final amplitude corresponding to the
changed power mode when changing the amplitude according to the
change in the power mode. In other words, the amplitude is slowly
increased or decreased across several display frames when switching
power modes.
[0210] Here, the intermediate amplitude corresponds to the
amplitude between the amplitude corresponding to the previous power
mode and the final amplitude corresponding to the changed power
mode.
[0211] FIG. 13a and FIG. 13b illustrate a phased amplitude control
method of the touch driving signal (TDS) according to the change in
the power mode (PM) in the display device 100, according to the
present embodiments. Here, it is assumed that there is one
intermediate amplitude in FIG. 13a and FIG. 13b.
[0212] Referring to FIG. 13a, when the frame 1 switches to the
frame 2, the adapter mode (AM) switches to the battery mode (BM)
and the frame 3 and the frame 4 remain in the battery mode
(BM).
[0213] In the touch mode period of the frame 1, in which the power
mode (PM) corresponds to the adapter mode (AM), the amplitude of
the touch driving signal (TDS), which is output from the touch
power integrated circuit 230, is .DELTA.Vac corresponding to the
adapter mode (AM).
[0214] In addition, in the touch mode period of the frame 2, in
which the power mode (PM) switches to the battery mode (BM), the
touch power integrated circuit 230 initially creates and outputs
the touch driving signal (TDS) that has the intermediate amplitude
(.DELTA.Vi) that is greater than the amplitude (.DELTA.Vac)
corresponding to the adapter mode (AM), and is less than the
amplitude (.DELTA.Vbc) corresponding to the battery mode (BM),
through the intermediate amplitude control.
[0215] In addition, in the touch mode period of the frame 3, in
which the power mode (PM) remains the battery mode (BM), the touch
power integrated circuit 230 creates and outputs the touch driving
signal (TDS) that has the final amplitude (.DELTA.Vbc)
corresponding to the battery mode (BM) by further increasing the
intermediate amplitude (.DELTA.Vi) through the intermediate
amplitude control.
[0216] In the touch mode period of the frame 4, in which the power
mode (PM) remains to be the battery mode (BM), the touch power
integrated circuit 230 outputs the touch driving signal (TDS) that
has the final amplitude (.DELTA.Vbc) corresponding to the battery
mode (BM).
[0217] Here, the touch mode period in the frame 2, in which the
touch power integrated circuit 230 creates and outputs the touch
driving signal (TDS) having the intermediate amplitude (.DELTA.Vi),
may be a sensing stabilization period for buffering the abrupt
change in the amplitude of the touch driving signal (TDS).
[0218] Although the touch driving signal (TDS) is applied to the
touch electrode (TE) in the sensing stabilization period, the touch
sensing process may not be performed.
[0219] Referring to FIG. 13b, when the frame 1 switches to the
frame 2, the battery mode (BM) switches to the adapter mode (AM)
and the frame 3 and the frame 4 remain in the adapter mode
(AM).
[0220] In the touch mode period of the frame 1, in which the power
mode (PM) corresponds to the battery mode (BM), the amplitude of
the touch driving signal (TDS), which is output from the touch
power integrated circuit 230, is .DELTA.Vbc corresponding to the
battery mode (BM).
[0221] In addition, in the touch mode period of the frame 2, in
which the power mode (PM) switches to the adapter mode (AM), the
touch power integrated circuit 230 initially creates and outputs
the touch driving signal (TDS) having the intermediate amplitude
(.DELTA.Vd), which is less than the amplitude (.DELTA.Vbc)
corresponding to the battery mode (BM), but is greater than the
amplitude (.DELTA.Vac) corresponding to the adapter mode (AM),
through the intermediate amplitude control.
[0222] In addition, in the touch mode period of the frame 3, in
which the power mode (PM) remains the adapter mode (AM), the touch
power integrated circuit 230 creates and outputs the touch driving
signal (TDS) that has the final amplitude (.DELTA.Vac)
corresponding to the adapter mode (AM) by further reducing the
intermediate amplitude (.DELTA.Vd) through the intermediate
amplitude control.
[0223] In the touch mode period of the frame 4, in which the power
mode (PM) remains the adapter mode (AM), the touch power integrated
circuit 230 outputs the touch driving signal (TDS) that has the
final amplitude (.DELTA.Vac) corresponding to the adapter mode
(AM).
[0224] Here, the touch mode period in the frame 2, in which the
touch power integrated circuit 230 creates and outputs the touch
driving signal (TDS) having the intermediate amplitude (.DELTA.Vd),
may be a sensing stabilization period for buffering the abrupt
change in the amplitude of the touch driving signal (TDS).
[0225] Although the touch driving signal (TDS) is applied to the
touch electrode (TE) in the sensing stabilization period, the touch
sensing process may not be performed.
[0226] According to the amplitude control method for the touch
driving signal (TDS) as described above, the touch driving signal
(TDS) having the desired amplitude (.DELTA.Vt) can be applied to
the touch electrode (TE), and thus, even with the change in the
power mode, and even in the battery mode (BM), the touch
sensitivity can be significantly improved.
[0227] Hereinafter, several touch sensitivity improving methods
will be further described in addition to the touch sensitivity
improving method through the amplitude control.
[0228] FIG. 14 is a view to explain the feedback capacitor (Cfb)
control method for improving the touch sensitivity in the display
device 100, according to the present embodiments.
[0229] Referring to FIG. 14, the touch circuit 210 may include the
amplifier 310, the integrator circuit 320, the analog-to-digital
converter 330, and the feedback capacitor (Cfb) as described
above.
[0230] The amplifier 310 is comprised of: the first terminal (n1)
that is electrically connected to the touch electrode (TE); the
second terminal (n2) to which the touch driving signal (TDS) is
applied; and the output terminal (n3) for outputting the touch
sensing signal (TSS).
[0231] The feedback capacitor (Cfb) is connected between the first
terminal (n1) and the output terminal (n3) of the amplifier
310.
[0232] The feedback capacitor (Cfb) may be, for example, a variable
capacitor that has a variable capacitance.
[0233] In addition, the feedback capacitor (Cfb) may be comprised
of a plurality of capacitors. In the case where the feedback
capacitor (Cfb) is the variable capacitor, it may be comprised of a
plurality of capacitors and a plurality of switches.
[0234] The integrator circuit 320 outputs an integral value of the
output voltage of the amplifier 310 {that is, the touch sensing
signal that is output from the output terminal (n3) of the
amplifier 310}. Such an integrator circuit 320 may be comprised of
devices, such as comparators or capacitors.
[0235] The analog-to-digital converter (ADC) 330 converts the
output voltage (the integral value) of the integrator circuit 320
into a digital value, and outputs the same as a sensed value.
[0236] Referring to FIG. 14, the amplitude of the touch driving
signal (TDS), which is input to the second terminal (n2) of the
amplifier 310 in the touch circuit 210, is the amplitude (.DELTA.V)
that is controlled by the touch power integrated circuit 230.
[0237] If the power mode (PM) switches from the battery mode (BM)
to the adapter mode (AM), the amplitude of the touch driving signal
(TDS), which is input to the second terminal (n2) of the amplifier
310, may be the amplitude (.DELTA.Vac) corresponding to the adapter
mode (AM) or the intermediate amplitude (.DELTA.Vd).
[0238] If the power mode (PM) switches from the adapter mode (AM)
to the battery mode (BM), the amplitude of the touch driving signal
(TDS), which is input to the second terminal (n2) of the amplifier
310, may be the amplitude (.DELTA.Vbc) corresponding to the battery
mode (BM) or the intermediate amplitude (.DELTA.Vi).
[0239] Referring to FIG. 14, as another method for improving the
touch sensitivity, it is possible to control the capacitance of the
feedback capacitor (Cfb).
[0240] To this end, the micro-control unit 220 may output a
capacitance control signal (CCS) for controlling the capacitance of
the feedback capacitor (Cfb) in the touch circuit 210 to the touch
circuit 210.
[0241] For example, the amplitude of the output signal (output
voltage) of amplifier 310 may increase by reducing the capacitance
of the feedback capacitor (Cfb) in order to thereby obtain a
greater sensed value so that the touch sensitivity may be
improved.
[0242] The degree of reduction in the capacitance of the feedback
capacitor (Cfb) may be limited by the output range of the amplifier
310, and may be appropriately configured in consideration of the
amount of reduction in the amplitude of the touch driving signal
(TDS). For example, the capacitance can be set to a high
capacitance level during adapter mode. The capacitance can be set
to a low capacitance level during battery mode in order to increase
touch sensitivity.
[0243] In order to control the capacitance of the feedback
capacitor (Cfb), the feedback capacitor (Cfb) may be implemented to
be a variable capacitor.
[0244] As described above, the control of the capacitance of the
feedback capacitor (Cfb) may further improve the touch sensitivity,
and may further expect the improvement of the touch sensitivity in
the battery mode (BM) in which the reduction in the amplitude of
the touch driving signal (TDS) may occur.
[0245] FIG. 15 is a view to explain a method for controlling the
integrator circuit 320 in order to improve the touch sensitivity in
the display device 100, according to the present embodiments.
[0246] Referring to FIG. 15, as another method for improving the
touch sensitivity, it is possible to control the number of
integration times of the integrator circuit 320 in the touch
circuit 210.
[0247] To this end, the micro-control unit 220 may output an
integrator control signal (ICS) for controlling the number of
integration times of the integrator circuit 320 to the touch
circuit 210.
[0248] Here, the degree of controlling the number of integration
times of the integrator circuit 320 may be configured to account
for the amount of reduction in the amplitude of the touch driving
signal (TDS) in the battery mode (BM). For example, the number of
integration times can be set to a low number of integration times
during adapter mode. The number of integration times can be set to
a high number of integration times during battery mode in order to
increase touch sensitivity.
[0249] The integrator circuit 320 outputs an integral value of the
voltage of the output terminal (n3) of the amplifier 310, and at
this time, if the number of integration times increases according
to the integrator control signal, the output integral value may
increase in order to thereby obtain a greater sensed value.
According to this, the touch sensitivity may be further
improved.
[0250] Such improvement of the touch sensitivity may be more
prominent in the battery mode (BM) in which the reduction in the
amplitude of the touch driving signal (TDS) may occur.
[0251] FIG. 16 is a view to explain a method of correcting a sensed
value for improving the touch sensitivity in the display device
100, according to the present embodiments.
[0252] Referring to FIG. 16, the micro-control unit 220 may perform
a touch algorithm for recognizing the touch or calculating the
touch coordinates by using a corrected sensed value that is
obtained by adding a predetermined correction value to a sensed
value output from the analog-to-digital converter (ADC) 330 instead
of recognizing the touch or calculating the touch coordinates by
using the sensed value corresponding to the digital value output
from the analog-to-digital converter (ADC) 330 in the touch circuit
210.
[0253] Here, the predetermined correction value may be calculated
and configured to be a value corresponding to the amount of
reduction in the amplitude of the touch driving signal (TDS). For
example, the correction value may be set to a low value (e.g. zero)
during adapter mode. The correction value may be set to a high
value during battery mode in order to increase touch
sensitivity.
[0254] The touch sensitivity may be improved through the correction
of the sensed value described above.
[0255] In particular, in the case where the amplitude of the actual
touch driving signal (TDS) applied to the touch electrode (TE) is
reduced compared to the amplitude of the touch driving signal (TDS)
output from the touch power integrated circuit 230 in the battery
mode (BM), the operation of performing the touch algorithm by using
the corrected sensed value, which is corrected through the
correction of the sensed value, may further increase the accuracy
of the touch sensitivity.
[0256] Various methods for improving the touch sensitivity, and the
display device 100 and the touch system 200 for the same have been
described above. Hereinafter, the elements included in the touch
system 200 will be described.
[0257] FIG. 17 illustrates the touch power integrated circuit 230,
according to the present embodiments.
[0258] Referring to FIG. 17, the touch power integrated circuit
230, according to the present embodiments, may create the touch
driving signal (TDS) to drive the touch electrode (TE), and may
include a signal generating unit 1710 that generates the touch
driving signals (TDS) that have different amplitudes according to
the power mode (PM) and a signal supplying unit 1720 that supplies
the created touch driving signals (TDS) to the touch circuit
210.
[0259] Since the touch driving signals (TDS) having different
amplitudes may be intentionally varied according to the power mode
(PM) by using the touch power integrated circuit 230 above, the
reduction in the amplitude of the touch driving signal (TDS), or
the touch sensitivity deviation thereof according to the power mode
(PM), may be prevented, and thus, the degradation of the touch
sensitivity or the touch sensitivity deviation depending on the
power mode (PM) may be prevented in order to thereby improve the
touch sensitivity.
[0260] The signal generating unit 1710 described above may receive
the amplitude control signal (ACS), which contains at least one
piece of the power mode (PM) information or the amplitude control
amount information, from the micro-control unit 220, and may create
the touch driving signal (TDS).
[0261] When the power mode (PM) is changed, the signal generating
unit 1710 mentioned above may change the amplitude of the touch
driving signal (TDS) step by step to then be output to the touch
circuit 210.
[0262] More specifically, when the power mode (PM) switches from
the adapter mode (AM) to the battery mode (BM), the signal
generating unit 1710 may increase the amplitude (.DELTA.Vac) of the
touch driving signal (TDS) to the amplitude (.DELTA.Vbc)
corresponding to the battery mode (BM) through one or more
intermediate amplitudes (.DELTA.Vi) whenever creating the touch
driving signal (TDS).
[0263] When the power mode (PM) switches from the battery mode (BM)
to the adapter mode (AM), the signal generating unit 1710 may
decrease the amplitude (.DELTA.Vbc) of the touch driving signal
(TDS) to the amplitude (.DELTA.Vac) corresponding to the adapter
mode (AM) through one or more intermediate amplitudes (.DELTA.Vd)
whenever creating the touch driving signal (TDS).
[0264] As described above, with regard to the creation of the touch
driving signal (TDS), the signal generating unit 1710 may create
the touch driving signal (TDS), which has the amplitude that
changes step by step, through the phased change in the amplitude
when the power mode switches, in order to thereby prevent an abrupt
change in the amplitude of the touch driving signal (TDS) according
to the change in the power mode so that stability of the touch
sensing may be improved.
[0265] FIG. 18 illustrates the micro-control unit 220, according to
the present embodiments.
[0266] Referring to FIG. 18, the micro-control unit 220, according
to the present embodiments, may include a power mode recognition
unit 1810 that detects the power mode (PM) and a control unit 1820
that outputs, to the touch power integrated circuit 230, the
amplitude control signal (ACS) that controls the touch power
integrated circuit 230 to create the touch driving signals (TDS)
that have different amplitudes depending on the power mode
(PM).
[0267] The touch power integrated circuit 230 may detect the power
mode (PM) in order to control (adjust) the amplitude of the touch
driving signal (TDS) according to the power mode by using the
aforementioned micro-control unit 220.
[0268] The amplitude control signal (ACS) mentioned above may
contain at least one piece of power mode information (power mode
change information) or the amplitude control amount information
(amplitude-increased amount information or amplitude-reduced amount
information).
[0269] The power mode recognition unit 1810 mentioned above may
detect the power mode (PM) to be one of the adapter mode (AM) or
the battery mode (BM) based on the input power voltage (VLED) of
the backlight driver.
[0270] As described above, when the input power voltage (VLED) of
the backlight driver is identified, the power mode recognition unit
1810 may detect the power mode (PM) to be one of the adapter mode
(AM) or the battery mode (BM). The power mode recognition unit 1810
may efficiently detect the power mode (PM) by using the power
system environment in the display device 100.
[0271] In addition, the power mode recognition unit 1810 may
receive the power mode information from the power system 410 in
order to thereby detect the power mode (PM) to be one of the
adapter mode (AM) or the battery mode (BM).
[0272] As described above, since the micro-control unit 220 may
receive the power mode information from the power system 410, which
can directly identify the supply of the power through the adapter
412, to detect the power mode (PM), it may be easy to detect the
power mode.
[0273] Meanwhile, when the power mode (PM) is detected to be the
battery mode (BM), the control unit 1820 of the micro-control unit
220 may create and output an amplitude control signal the (ACS) for
increasing the amplitude of the touch driving signal (TDS).
[0274] Accordingly, the touch driving signal (TDS) that has the
greater amplitude (.DELTA.Vbc) may be created in the battery mode
(BM), compared to the adapter mode (AM), so that the reduction in
the amplitude of the touch driving signal (TDS), which occurs in
the course of transmitting the touch driving signal (TDS), may be
compensated, and thus, the touch sensitivity in the battery mode
(BM) may be improved.
[0275] Meanwhile, in consideration of the change in the power mode,
when the power mode (PM) is detected to change from the adapter
mode (AM) to the battery mode (BM), the control unit 1820 may
output an amplitude control signal (ACS) for increasing the
amplitude of the touch driving signal (TDS).
[0276] In addition, when the power mode (PM) is detected to change
from the battery mode (BM) to the adapter mode (AM), the control
unit 1820 may output an amplitude control signal (ACS) for reducing
the amplitude of the touch driving signal (TDS).
[0277] According to the description above, the effective amplitude
control may be performed to conform to the power mode changing
situation in order to thereby provide an excellent touch
sensitivity in any power mode changing situation.
[0278] Meanwhile, when the power mode (PM) is detected to change
from the adapter mode (AM) to the battery mode (BM), the control
unit 1820 may output an amplitude control signal (ACS) that allows
the amplitude of the touch driving signal (TDS) to increase to the
amplitude (.DELTA.Vbc) corresponding to the battery mode (BM)
through one or more intermediate amplitudes (.DELTA.Vi).
[0279] When the power mode (PM) is detected to change from the
battery mode (BM) to the adapter mode (AM), the control unit 1820
may output an amplitude control signal (ACS) that allows the
amplitude of the touch driving signal to decrease to the amplitude
(.DELTA.Vac) corresponding to the adapter mode (AM) through one or
more intermediate amplitudes (.DELTA.Vd).
[0280] By using the aforementioned micro-control unit 220, an
abrupt change in the amplitude of the touch driving signal (TDS)
may be prevented through the phased change in the amplitude so that
the instability of the touch sensing may be mitigated.
[0281] Meanwhile, the control unit 1820 may determine the
amplitude-increased amount information or amplitude-reduced amount
information based on the touch sensing signal (TSS) received
through the touch electrode (TE) to which the touch driving signal
(TDS) is applied, and may create and output an amplitude control
signal (ACS) that contains the determined amplitude-increased
amount information or amplitude-reduced amount information.
[0282] As described above, it may be whether or not the amplitude
of the actual touch driving signal (TDS) applied to the touch
electrode (TE) reaches a desired amplitude (.DELTA.Vt) as a result
of the amplitude control is detected, through the touch sensing
signal (TSS), in order to thereby re-adjust the amplitude of the
actual touch driving signal (TDS) applied to the touch electrode
(TE) until it reaches the desired amplitude (.DELTA.Vt). According
to this, it is possible to make an accurate amplitude control so
that the touch sensitivity may be further improved.
[0283] FIG. 19 illustrates the touch circuit 210, according to the
present embodiments.
[0284] Referring to FIG. 19, the touch circuit 210, according to
the present embodiments, may include the amplifier 310, the
integrator circuit 320, the analog-to-digital converter 330, and
the feedback capacitor (Cfb).
[0285] The amplifier 310 is comprised of: the first terminal (n1)
that is electrically connected with the touch electrode (TE); the
second terminal (n2) to which the touch driving signal (TDS) is
applied; and the output terminal (n3) that outputs the touch
sensing signal (TSS).
[0286] The feedback capacitor (Cfb) is connected between the first
terminal (n1) and the output terminal (n3) of the amplifier
310.
[0287] The feedback capacitor (Cfb) may be a fixed capacitor that
has a fixed capacitance, or may be a variable capacitor that has a
variable capacitance.
[0288] In addition, the feedback capacitor (Cfb) may be comprised
of a plurality of capacitors. In the case where the feedback
capacitor (Cfb) is the variable capacitor, it may be comprised of a
plurality of capacitors and a plurality of switches.
[0289] The integrator circuit 320 outputs an integral value of the
output voltage of the amplifier 310 {that is, the touch sensing
signal that is output from the output terminal (n3) of the
amplifier 310}. Such an integrator circuit 320 may be comprised of
devices, such as comparators or capacitors.
[0290] The analog-to-digital converter (ADC) 330 converts the
output voltage (the integral value) of the integrator circuit 320
into a digital value, and outputs the same as a sensed value.
[0291] The touch driving signals (TDS), which are input to the
second terminal (n2) of the amplifier 310, have amplitudes
(.DELTA.V) controlled by the touch power integrated circuit
230.
[0292] In addition, the touch driving signals (TDS), which are
input to the second terminal (n2) of the amplifier 310, have
different amplitudes depending on the power mode (PM).
[0293] By using the aforementioned touch circuit 210, the touch
drive may be performed by using the touch driving signals (TDS)
that are intentionally created to have different amplitudes
depending on the power mode (PM), so that the reduction in the
amplitude of the touch driving signal (TDS) or the amplitude
reduction deviation depending on the power mode (PM) may be
prevented in order to thereby improve the touch sensitivity.
[0294] Such a touch circuit 210 may be included in the driving
integrated circuit together with a data driving circuit.
[0295] This will be described with reference to FIG. 20.
[0296] FIG. 20 is a view illustrating a driving integrated circuit
2000, according to the present embodiments.
[0297] The driving integrated circuit 2000 in FIG. 20, according to
the present embodiments, may include: a touch circuit 210 that
receives the touch driving signals (TDS), which have different
amplitudes according to the power mode (PM), and sequentially
outputs the same to a plurality of touch electrodes (TE) embedded
in the display panel 110 in the touch mode period; a common voltage
supply circuit 2010 that supplies a common voltage (Vcom) to the
plurality of touch electrodes (TE) in the display mode period; and
a data driving circuit 2020 that drives a plurality of data lines
(DL) disposed in the display panel 110 in the display mode
period.
[0298] The aforementioned driving integrated circuit 2000 is an
integrated circuit in the form of a combination of the source
driver integrated circuit 450 of FIG. 4 and the touch circuit
210.
[0299] In the case of using the driving integrated circuit 2000,
there is no need to separately provide the source driver integrated
circuit 450 for driving the display, such as the data driving, and
the touch integrated circuit for the touch driving and sensing, in
order to thereby reduce the number of components.
[0300] In particular, in the case where the touch electrode (TE) is
the mode common electrode that is used in both the display mode and
the touch mode, the driving integrated circuit 2000 in an
integrated form may provide the display driving and the touch
driving more effectively.
[0301] The present embodiments, as described above, can provide a
differentiated touch drive according to the power mode in order to
thereby improve the touch sensitivity.
[0302] In addition, according to the present embodiments, when the
power mode corresponds to the battery mode, the degradation of the
touch sensitivity can be prevented.
[0303] Furthermore, according to the present embodiments, when the
power mode switches, the touch sensitivity can be improved through
an adaptive touch drive.
[0304] The above description and the accompanying drawings provide
an example of the technical idea of the present invention for
illustrative purposes only. Those having ordinary knowledge in the
technical field, to which the present invention pertains, will
appreciate that various modifications and changes in form, such as
combination, separation, substitution, and change of a
configuration, are possible without departing from the essential
features of the present invention. Therefore, the embodiments
disclosed in the present invention are intended to illustrate the
scope of the technical idea of the present invention, and the scope
of the present invention is not limited by the embodiment. The
scope of the present invention shall be construed on the basis of
the accompanying claims in such a manner that all of the technical
ideas included within the scope equivalent to the claims belong to
the present invention.
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